In the field of printed circuit board manufacturing there are commonly employed photosensitive elements obtained by forming photosensitive resin compositions and layers composed of photosensitive resin compositions (hereinafter referred to as “photosensitive resin composition layers”) onto support films, as resist materials for etching or plating, and covering the photosensitive resin composition layers with protective films.
Such a photosensitive element is used to fabricate a printed circuit board by the following procedure, for example. Specifically, first the photosensitive resin composition layer of the photosensitive element is laminated onto a circuit-forming board. The side of the photosensitive resin composition layer opposite the side in contact with the support film is contact bonded to the side of the circuit-forming board on which the circuit is to be formed. When the protective film is positioned on the side which is to be contacted bonded with the photosensitive resin composition layer, therefore, the lamination operation is carried out while peeling off the protective film. Next, exposure is performed through a mask film or the like to form an image (pattern), and then the unexposed sections are removed with a developing solution to form a resist pattern. The resist pattern is in turn used as a mask for etching or plating, in order to form a circuit, and finally the cured sections are released and removed from the base.